Conventionally, a reduction in the amount of lead to be used in semiconductor devices has been demanded from the viewpoint of environmental load.
In the semiconductor device, for example, lead has been used for outside components to be used outside the device, such as an exterior plating of an outer lead in an SOP (Small Outline Package) or a QFP (Quad Flat Package) and a solder ball in a BGA (Ball Grid Array). Lead has also been used for an inside component to be used inside the device such as a bonding material between a semiconductor chip and lead frame in the inside of the package.
Lead-freeing to make the content of lead to a fixed ratio or less has almost been achieved for the outer components through research of substitute materials. On the other hand, there is no material suitable as a substitute for the inside components. Therefore, for example, Pb-xSn-yAg (x and y are positive numbers), a lead-containing metal has been used.